kirkham



UNITED STATES PATENT OFFICE.

WM. S. KIRKHAM, OF BRANTFORD, CONNECTICUT.

LOCK.

Specification of Letters Patent No. 30,580, dated November 6, 1860.

To all 'whom 'if may concern:

Be it known that I, W. S. KIRKHAM, of Brantford, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Locks; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this specification, in which- Figure l, is a side view of a lock constructed according to my invention with the side of the casing nearest the eye removed in order to show the interior. Fig. 2, a section of the saine taken in the line ce, Fig. l. Fig. 3, a horizontal section of the same, taken in the line y, y, Fig. l. Fig. el, a side view of an ordinary lock drawn to show the difference between it and my invention.

Similar letters of reference indicate corre spending parts in the several drawings.

The object of this invention is to obtain an equal action of the knob-hub upon the slide of a lock when the knob is turned in either' direction, that is to say, having the parts which connect the knob with the slide or latch so arranged that the slide will be actuated or drawn back within the lock case with the same facility and application of power when the knob is turned in either direction.

The invention consists in the employment or use of a yoke, lever, spring and slide, arranged as hereinafter fully shown and de.- scribed to effect the desired end.

To enable those skilled in the art to fully understand and construct my invention I will proceed to describe it.

A, Figs. l, 2 and 3, representsthe case of a lock, and B, the bolt. These parts being of ordinary construction do not require a minute description. C, is the slide or latch of the lock which may be of the usual form and fitted between guides tt, a, in the ordinary way. D, is the hub through which the knob arbor E, passes. This hub is fitted within a sliding yoke F, and the arms of the hub act against projections c, c, on the yoke F. To the yoke F, a lever G, is attached by a pin d. The upper end of this lever is notched to receive a projection e, at the upper part of the case said projection serving as a fulcrum for the lever. The upper end of the lever G, has the upper end of a bent spring H, bearing against it, and the lower end of the lever G, is fitted in a hole in the slide C.

By referring to Fig. 1, it will be seen that the spring H, has a tendency to keep the slide C, forced out from the case A, and it will also be seen that by turning the hub I), in either direction the same power is applied to the slide C, the leverage being the same whether the upper or lower arm b, throws back the yoke F. By this arrangement therefore a great advantage is obtained, the lock may be manipulated with greater facility it being perfectly immaterial in which direction the knob is turned as the slide is thrown back with precisely the same application of power in either CASS.

The ordinary lock, as shown in Fig. il, has its hub I, arranged with a lever J, the fulcrum of which is at The arms (7, g, of the hub I, act direct-ly against the lever J, and itwill be seenv that when the lower arm of the hub acts against the lever the slide K, will be moved with a slight application of power because the leverage is great, when however the upper arm g, acts against the lever J, considerable power is required to throw back the slide because the leverage is small. This arrangement also does not ad mit of the hub being placed as near the back edge of the case as the hub in my invention, for in the former case space must be allowed for the play or movement of lever J.

The knob -arbor therefore requires to be placed nearer the front edge of the lock than the key hole L.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is-

The arrangement of the sliding yoke F, lever G, spring I-I, and slide or latch C, essentially as and for the purpose set forth.

WM; S. KIRKHALI.

Witnesses:

SAMUEL BEACH, F. A. HoLcoMB. 

